One-dimensional (1D) bar codes are machine-readable objects used to store information about a product, package, or other item upon which the 1D bar code is affixed. 1D bar codes store information only in the horizontal direction, and laser scanners are often used to read and decode these bar codes. Such laser, or “point,” scanners exhibit a high motion tolerance making them ideal for accurately decoding 1D bar codes.
But 1D bar codes are limited in application due to the small amount of information they contain. 1D bar codes store information only in one dimension, merely encoding a number or other identifier that, after decoding, must be compared to an external database containing relevant information. For example, after decoding 1D bar code encoding a product identifier, a computer may retrieve the price, quantity, or other relevant information about the product from an external database.
Due to the limited application of 1D bar codes, two-dimensional (2D) bar codes have recently grown in popularity. Unlike 1D bar codes, 2D bar codes contain information in both the horizontal and vertical directions, storing more information than 1D bar codes. This requires sophisticated 2D imagers to decode the entire image at once. Such imagers have a low motion tolerance, as any movement of the bar code or imager during image capture causes the image as a whole to blur, resulting in sluggish read rates.